A team of scientists say they’We’ve found a new way to help people with damaged corneas: bio-engineered implants created from pigskin. In the results of a small clinical trial published this month, the implants were shown to restore people’s sight for up to two years, including those who were legally blind. If it continues to show promise, the technology could one day provide a mass-produced alternative to human cornea donations for people with these conditions.
The cornea is the transparent outer covering of the eye. In addition to protecting the rest of the eye, it helps us see by focusing the light that passes through it. Corneas can heal fairly easily from minor abrasions, but more severe injuries and some diseases can leave behind permanently damaged corneas that begin to impair our sight. About 4 million people are thought to suffer from vision problems caused by injured corneas, according to the World Health Organization, and it is one of the leading causes of blindness.
For those with severely damaged corneas, the only truly effective treatment is a transplant from a healthy cornea, also known as a corneal transplant. Unfortunately, like many organs, human corneas must be used very soon after donation. and they are often rare, especially for people living in poorer countries. This scarcity has fueled researchers’ efforts to find other methods to replace or support damaged corneas. One such approach is the implant created by researchers at Linköping University (LiU) in Sweden, who also founded the company LinkoCare Life Sciences AB to develop it further.
In their to research, published last week in Nature Biotechnology, the team gave their implant to 20 patients from India and Iran with advanced keratoconus, a condition where the cornea gradually thins. Nineteen of the 20 patients experienced substantial improvements in their sight afterwards, with the 14 legally blind people no longer meeting this threshold. Patients who needed additional corrective treatment were also able to tolerate contact lenses again. And these gains have remained stable two years later, while no adverse events have been reported.
“The results show that it is possible to develop a biomaterial that meets all the criteria to be used as a human implant, which can be mass-produced and stored for up to two years and thus reach even more people with health problems. vision,” said the study’s author. Mehrdad Rafat, Professor in the Department of Biomedical Engineering at LiU and CEO of LinkoCare, in a statement of the University.
It exists artificial corneas in use, as well as similar treatments under development. But the researchers say their implant should have some key advantages over these options. Many of these treatments still rely on donated corneas to reduce the risk of rejection by the body, while the team’s implant instead uses a relatively inexpensive biosynthetic material derived from purified pigskin. The material is then used to create a thin but durable layer made up primarily of collagen, the same basic ingredient of the cornea. In the current study, patients received only eight weeks of transplant drugs to ensure acceptance by the body, as opposed to year or more of drugs usually given to those who have corneal transplants, and no signs of rejection have been reported.
They also developed a less invasive surgical method to insert their implant, which does not need to remove the original cornea, which should reduce the risk of complications and allow wider use in places with fewer resources. And other research suggests that the implant materials should remain stable for at least eight years, possibly longer.
“We have gone to great lengths to ensure that our invention will be widely available and affordable to everyone, not just the wealthy. This is why this technology can be used in all parts of the world,” Rafat said.
Of course, these results are still very limited. It will take positive results seen in many more patients before a country thinks of approving this treatment. To that end, the researchers are planning larger clinical trials of their implant, and they may expand their work to see if the treatment can work for other corneal-related conditions.